1. Field of the Invention
The present invention relates to an improvement in a fuel rail/fuel conduit connecting structure in an engine for an outboard engine system, in which fuel rails mounted to a plurality of fuel injection valves in the engine for the outboard engine system are connected with fuel conduits for delivering and receiving fuel to and from the fuel rails in order to dispense the fuel to the fuel injection valves in the engine.
2. Description of the Related Art
A conventional fuel rail/fuel conduit connecting structure in an engine for an outboard engine system is already known, as disclosed, for example, in Japanese Patent Application Laid-open No. 2000-34934.
In the fuel rail/fuel conduit connecting structure disclosed in the above Japanese Patent Application Laid-open No. 2000-34934, a connecting flange of a joint connected to the fuel conduit is secured by a pair of bolts to a side of the fuel rail into which a fuel port opens, whereby the inside of the joint is put into communication with the fuel port. This structure is accompanied by the following disadvantage: An end of a fuel passage opening into an end face of the fuel rail must be occluded by a special blind plug and moreover, the two bolts are required to secure the joint to the fuel rail. Therefore, the number of parts and the number of assembling steps are increased, and it is difficult to reduce the cost.
Accordingly, it is an object of the present invention to provide a fuel rail/fuel conduit connecting structure in an engine for an outboard engine system, wherein the connection of the fuel rail and the fuel conduit can be carried out, while providing reductions in number of parts and number of assembling steps and moreover, the structure has excellent corrosion resistance.
To achieve the above object, according to a first aspect and feature of the present invention, there is provided a fuel rail/fuel conduit connecting structure in an engine for an outboard engine system, the structure providing a connection between: a fuel rail mounted to a plurality of fuel injection valves in the engine in order to dispense a fuel to the fuel injection valves; and fuel conduits for delivering and receiving the fuel to and from the fuel rail; wherein a first connecting bore opens into an end face of the fuel rail and leads to a fuel passage in the fuel rail, and a second connecting bore opens into an end face of a synthetic resin terminal member having a connecting pipe portion which is projectingly provided on one side of the terminal member and to which an end of the fuel conduit is connected, the second connecting bore leading to the inside of the connecting pipe portion; wherein one of halves of a joint collar is fitted to an inner peripheral surface of the first connecting bore with a first seal member interposed therebetween, and the other half of the joint collar is fitted to an inner peripheral surface of the second connecting bore with a second seal member interposed therebetween; and wherein the fuel rail and the fuel conduit are fastened to each other with their end faces aligned with each other by a single bolt.
The fuel conduits correspond to a communication pipe 112 and a third fuel conduit 123 in an embodiment of the present invention, which will be described hereinafter.
With such arrangement of the first feature, the terminal member fitted over the other half of the joint collar functions as a cap for covering an end face of each of the fuel rails and hence, a special closing member for occluding the fuel rails of the fuel rails as in the conventionally known structure is not required. In addition, the joint collar fitted into the first and second connecting bores not only permits each of the fuel rails and the terminal member to communicate with each other, but also prevents the rotation of the terminal member by cooperation with the single bolt and hence, the terminal member can be fastened to each of the fuel rails by the single bolt. Thus, it is possible to reduce the number of parts and the number of assembling steps for the connecting structure, leading to a reduction in cost.
In addition, the seal member is interposed between the outer peripheral surface of the joint collar and the inner peripheral surface of each of the first and second connecting bores and hence, even if there is a dislocation of the coaxial disposition of the first and second connecting bores, such dislocation can be absorbed by the deformation of the seal members to ensure the liquid tightness around the joint collar.
Further, the terminal member is made of a synthetic resin having a corrosion resistance and hence, even if seawater or the like is deposited to the terminal member, there is not a possibility that the terminal member is corroded.
According to a second aspect and feature of the present invention, in addition to the first feature, wherein a distance collar made of a metal is embedded in the terminal member, the bolt being inserted through the distance collar.
With such arrangement of the second feature, it is possible to firmly clamping the terminal member made of the synthetic resin to each of the fuel rails with a clamping force of the bolt shared by the distance collar.
The above and other objects, features and advantages of the invention will become apparent from the following description of the preferred embodiment taken in conjunction with the accompanying drawings.